The iPad 2,4 Review: 32nm Brings Better Battery Life
by Anand Lal Shimpi on May 4, 2012 12:50 AM ESTDecreased Power Consumption
We obviously know the impact of the new SoC on battery life but here's a look at just how much less power the new platform draws in various conditions. Note that for whatever reason the iPad's power consumption when sitting at the home screen is actually higher than when running our 720p High Profile video playback test. The results were consistent as I tested multiple times across multiple iPads. I have a few thoughts as to what could be happening here:
| Tablet Power Consumption (including Display) | ||||||
| iPad 2,4 | iPad 2 | iPad (3rd generation) | ||||
| Homescreen | 2.7 W | 2.9 W | 6.1 W | |||
| Sunspider | 3.4 W | 4.3 W | 7.6 W | |||
| Moonbat (20 x 4) | 3.9 W | 5.0 W | 8.3 W | |||
| GLBench Egypt (native res) | 3.8 W | 4.5 W | 9.6 W | |||
| GLBench Egypt (offscreen 720p) | 4.1 W | 4.8 W | 10.0 W | |||
| Infinity Blade 2 | 4.3 W | 5.1 W | 10.3 W | |||
| Riptide GP | 3.9 W | 4.7 W | 10.2 W | |||
| Video Playback (720p HP) | 2.2 W | 2.4 W | 4.9 W | |||
Under heavy CPU load (multithreaded Sunspider) we see a 28% increase in power consumption from the 45nm iPad 2,1 compared to the newer 2,4. Keep in mind that we're looking at peak power consumption here, which helps explain the smaller gap on the GPU side than what we saw in our battery life tests. What this data does show however is that the power efficiency improvements can be just as significant for CPU bound workloads, it's simply harder to find workloads that are CPU bound for long periods of time.
Looking at the 3rd generation iPad data reminds us of just how power hungry that platform is. It truly is Apple's performance halo, and it's the perfect target for a 32nm SoC in the future.
The iPad 2 battery life comparison numbers were generated on a lightly used iPad 2 with fewer than 20 charge cycles. While it's possible that some of the differences highlighted on the previous page are due to differences in the batteries between these two devices, it's likely that the variance is in the single digit range at best due to the limited number of charge cycles on the iPad 2 (Update: we confirmed the delta between our iPad 2 results and a brand new, out of box 45nm iPad 2 was < 3%). The power consumption numbers above remove the battery from the equation and help to validate these numbers.
Slightly Improved Thermals
I ran the same temperature test I did for our iPad review: measure maximum surface temperature of the tablet after a 1 hour loop of Infinity Blade 2. The results aren't surprising:
| Thermal Comparison (Max Temperature) | ||||||
| iPad 2,4 | iPad 2 | iPad (3rd generation) | ||||
| Infinity Blade 2 (1 hour) | 33.2˚C | 34.2˚C | 41.9˚C | |||
The iPad 2,4 manages to shave off a degree of surface temperature. It's not really noticeable, but it's there.
Performance
There's no performance difference between the iPad 2,4 and the older iPad 2 models. Regardless of whether you're looking at CPU or GPU performance, the new and older iPad 2s are indistinguishable. Apple definitely embraced the console mentality with this launch.
One difference you will notice between iPads however is variance in the panel vendor and resulting performance. Similar to what we've reported on in the Mac space, Apple likes to get 2 - 3 vendors for most components with very few exceptions (e.g. the CPU/GPU/SoC). We've seen this primarily be an issue with displays and storage devices in Macs, but on the iPad/iPhone side of the fence it can definitely be noticeable as the display plays such a major role in the experience with these devices.
The iPad 2,4 I'm reviewing has noticeably different display characteristics compared to my older iPad 2. My 2,4 sample has a higher maximum brightness (and black level), better grayscale color accuracy, and lower color temperature (more yellow). The new panel isn't any worse than what we've reviewed previously, in fact it's actually slightly better in a number of areas, although some users may be put off by the lower white point temperature (6200K vs. 6600K).
The panel I ended up with here isn't specific to the 2,4, but rather something you could end up with in any iPad 2 model. This is nothing new, but it's always interesting to get an idea of the amount of variance Apple considers acceptable. The new iPad still appears to be in the single or dual source stage (there's conflicting information about whether or not LG made panels are also available today). Sharp is expected to come online in the near future as another source. It remains to be seen how those panels will fare compared to the excellent Samsung panel that Apple launched with however.
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LittleMaNiaC - Monday, June 11, 2012 - link
HI guys! I would like to ask you all. Those who bought ipad 2,4 are from U.S right? I wonder did any of those ipad 2,4 went to Asia?machugger - Wednesday, June 27, 2012 - link
Why would an iPad 2 w/serial no. starting w/"DM" that was manufactured1) in the same factory as the 2,4
AND
2) AFTER April, when the 2,4 models were made
…why would it be a 2,1?!?!?!?!?
marketjock - Monday, July 30, 2012 - link
From Apple's website, when adding the iPad 2 16GB to your cart, the part number MC954LL/A is used. Is it safe to say when looking for a new one, to only look for MC954LL/A as that will have the 32nm chip?marketjock - Monday, July 30, 2012 - link
From what I have read, it does not matter the part number or the S/N. Any can have the 45nm or 32nm chip. It appears to be a matter of exhausting out the 45nm inventory.TechKnow12 - Wednesday, August 1, 2012 - link
Hi,If anyone is after the iPad 2,4 please read the following.
If you're in the US, look for:
MC769LL/A, 16gb, Black - Serial prefixes: DMQH, DMPH - both proven to be 2,4
MC979LL/A, 16gb, White - Serial prefixes: DMQH, DMPH
MC954LL/A, 16gb, Black - new model number, serial prefix not known - proven to be 2,4
MC989LL/A, 16gb, White - unproven but as it's the new model number it should be 2,4
If you're in Australia, look for:
MC769X/A, 16gb, Black, Serial prefixes: DMQJ, DMPJ - proven to be 2,4 by me.
MC979X/A, 16gb, White, Serial prefixes: DMQJ, DMPJ
The MC954 & MC989 appear to be US only models.
Please note that the Australian models may possibly have the prefix with H at the end instead of J and vice versa for US.
If you live in Australia I can confirm that the Apple Store in Perth has the DMQJ & DMPJ in stock. I purchased mine from Big W however I had to check with 4 stores before I found a DMPJ.
Battery Life
Okay so now you're wondering if the alleged extended battery life of 11.7 hours makes this worth buying or not.
Well, out of the box my iPad 2,4 had a charge of 76% and for the next 2 hours, from setting up, to installing my Apps, to surfing the net the charge only dropped to 66%. Wow! Then I discovered that Bluetooth was switched on by default the entire time which would have no doubt added to the battery drain, thus I managed 10% battery usage in 2 hours using wifi and with Bluetooth on. Double wow! It has now been 7 hours since I first powered the iPad on and I'm only down to 43%. Bluetooth was turned off when I found it was on, of course. In that 7 hours the iPad wasn't in use for about 30 minutes (had to have a couple of breaks) so actual usage would be 6.5 hours.
So depending on how you use the iPad I'm thinking you may get a minimum of 11.7 hours general usage (therefore non gaming or video watching) and possibly a maximum of 20 hours general usage.
Lastly, if at some point down the track you decide to sell the iPad 2,4 (like when the iPad 4 with the Sharp IGZO screen gets released) I'm sure you'll be able to sell it on eBay for a good price.
Saint04 - Wednesday, August 1, 2012 - link
I can confirm your findings with the white iPad 2,4. I picked one up from Walmart today with a production year of 2012 in the month of June. The part # is MC979LL/A. However my serial prefix doesn't match your findings. My serial prefix is DYTH. I could have used your findings the day before yesteday. I went through four of these before getting ahold of an iPad 2,4. So far it runs great and I'm relieved to get ahold of one. I'll be selling my new iPad on ebay as the quicker charging time and battery life on the ipad 2 is more important to me at the momment. I use my iPad in classes (all day sometimes) to take notes, read course books and I don't always have access to an outlet. I'll be looking forward to the Gen 4 iPad and the iPad 2,4 will suffice for now.TechKnow12 - Thursday, August 2, 2012 - link
That's awesome Saint04. Glad to hear you found one! I know the feeling of being "relieved" at finding the 2,4. I set myself up to be disappointed when I purchased mine (expected only to have a 2,1) but then of course I was over the moon when Linpack revealed it was a 2,4. :DThanks very much for letting us know about the DYTH serial number prefix too! I'll pass on this valuable bit of info at other forums.
No doubt as the old stock of iPad 2's gets sold off it will become much easier to find the 2,4 and there will be a plethora of serial numbers to look out for.
Enjoy your 2,4 Saint04! And if you revisit this site, please let us know roughly what battery life you're getting. Thanks! :)
Saint04 - Monday, September 10, 2012 - link
Hey TechKnow12. The battery life was close to advertised in performance as what anandtech reported in the ipad 2, 4 article. I apologize for the late response, I didn't realize that I had one until I was reading back over the forum. Also, just purchased another ipad 2 with the MC979LL/A part number it too was the new ipad 2,4. Take care, grace and peace.boofarino - Saturday, August 18, 2012 - link
hi i just wanted to confirm that the serial code DMPH is accurate. I went to micro center in minneapolis and bought an ipad with serial DR, and it was an ipad 2,1. I returned it and purchased one from best buy in richfield. At first he also said they only had ones with the DR serial number but after asking him to check again he came back with a DMPH, the protective plastic was a bit ripped and dirty so maybe it was older stock, but on coming home and powering it on i was very happy to see that it was an ipad 2,4. thanks for all the help guys, especially Technow 12. very happy to have the one with extra battery life. And also when i was in the best buy store I was suprised to realise that there is a significant difference in weight when holding the ipad 2, and ipad 3, i know its meant to be imperceptible but the ipad 2 definitely feels lighter.Arpajon - Monday, October 22, 2012 - link
I've checked a couple of local stores this week and can find neither an MC769LL/MC979LL DMQH/DMPH nor an MC954LL/MC989LL. Has anyone in the States had any recent success in finding a 2,4?One other question... I've never owned an Apple iAnything - if the iPad Mini comes out tomorrow as rumored, is the iPad 2,X likely to be discounted immediately?